This application claims priority to German Patent Application No. 101 39 163.3 filed on Aug. 9, 2001, the disclosure of which is incorporated herein by reference.
The invention relates to fiber carding machines. More particularly, the invention relates to a device on a carding machine. The device has cover elements with openings arranged opposite the main carding cylinder clothing for separating out foreign particles such as trash, seed parts, leaf rests and the like through the openings.
A known device of this type, disclosed in German patent document DE 38 35 776, has a cleaning apparatus in the form of a suction unit, with a guide rod arranged in front and a cutter bar arranged behind the unit. The disadvantage of this device is that adjustments cannot be made to influence the composition of the waste material containing foreign particles that is separated out.
It is an object of the invention to create a device which avoids the aforementioned disadvantages and, in particular, makes it possible to change or influence the waste material composition and to adjust the waste material separation.
Particular embodiments of the invention provide a pressure control system for use with a carding machine having a carding cylinder with clothing. The pressure control system has a cover for positioning opposite the carding cylinder clothing, an opening in the cover for separating foreign particles from desirable fibers, and a replaceable pressure regulator mounted in the cover. The pressure regulator is for adjusting a pressure between the cover and the carding cylinder.
The composition of the waste leaving through the separation opening can be changed or influenced and an adjustment of the waste material separation can be made through adjusting the pressure between the cover and the main carding cylinder. One advantage is the optimization of the waste material separation, which improves the ratio between desired separation of foreign particles and undesirable removal of good fibers. In addition, the waste material separation can be better adapted to the fiber material (raw material) to be processed.
Embodiments of the invention provide a changeable element of a cover that is opposite the clothing of a carding cylinder. The cover element can be a throttle bar, wherein the distance between the throttle bar and the clothing can preferably be changed. It is advantageous if the pressure, as seen in rotational direction of the cylinder, is increased in front of the throttle bar and is reduced behind the throttle bar. The cover element can also be a fixed carding element with clothing. The distance between the clothing on the fixed carding element and the clothing on the main carding cylinder should be changeable. It is advantageous if the pressure, as seen in the rotational direction of the main carding cylinder, is increased in front of the fixed carding element and is reduced behind the fixed carding element. The cover element can also have an air flow opening, wherein the air flow opening preferably can be connected to a vacuum and/or compressed air source. The strength of this vacuum and/or compressed air source should be adjustable. It is advantageous if the size of the air flow opening can be changed, wherein the size of the opening can be advantageously used for realizing a pressure drop (in the case of excess pressure) or a pressure increase (in the case of low pressure).
Other embodiments of the invention provide a carding machine having a carding cylinder having clothing, and a pressure control system. The pressure control system has a cover for positioning opposite the carding cylinder clothing, an opening in the cover for separating foreign particles from desirable fibers, and a replaceable pressure regulator mounted in the cover. The pressure regulator adjusts a pressure between the cover and the carding cylinder.